DTC Description
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time. To judge the malfunctions of heated oxygen sensor 2, ECM monitors whether the switching response of the sensor's voltage is faster than specified during various driving conditions such as fuel cut.

| DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
| P0139 | HO2S2 (B1) (O2 sensor circuit slow response bank 1 sensor 2) | The switching time between rich and lean of a heated oxygen sensor 2 signal delays more than the specified time computed by ECM. |
POSSIBLE CAUSE
FAIL-SAFE
Not applicable
DTC CONFIRMATION PROCEDURE
1.INSPECTION START
Do you have CONSULT? Do you have CONSULT? YES >> GO TO 2.
NO >> GO TO 7.
2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
TESTING CONDITION: For better results, perform “DTC WORK SUPPORT� at a temperature of 0 to 30°C (32 to 86°F).
>> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
With CONSULT
CAUTION: Always drive vehicle at a safe speed.
CAUTION:

Is “CMPLT� displayed on CONSULT screen? YES >> GO TO 6.
NO-1: “CMPLT� is not displayed on DIAG 1>>Perform DTC confirmation procedure again.
NO-2: “CMPLT� is not displayed on DIAG 2>>GO TO 4.
4.PERFORM DTC WORK SUPPORT
NOTE: It will take at most 10 minutes until “COMPLETED� is displayed. Is “COMPLETED� displayed on CONSULT screen? YES >> GO TO 6.
NO >> GO TO 5.
5.PERFORM DTC CONFIRMATION PROCEDURE AGAIN
>> GO TO 3.
6.PERFORM SELF-DIAGNOSIS
With CONSULT
Perform ECM self-diagnosis.
Is DTC “P0139� detected? YES >> Proceed to EC-251, "Diagnosis Procedure".
NO >> INSPECTION END
7.PERFORM COMPONENT FUNCTION CHECK-1
Without CONSULT

Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 8.
8.PERFORM COMPONENT FUNCTION CHECK-2
Check the voltage between ECM harness connector and ground as per the following condition.

Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 9.
9.PERFORM COMPONENT FUNCTION CHECK-3
Check the voltage between ECM harness connector and ground as per the following condition.

Is the inspection result normal? YES >> INSPECTION END
NO >> Proceed to EC-238, "Diagnosis Procedure".
Diagnosis Procedure
1.CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
Is the 1st trip DTC P0171 or P0172 detected? Is it difficult to start engine? YES >> Perform trouble diagnosis for DTC P0171 or P0172. Refer to EC-260, "DTC Description" or EC- 265, "DTC Description".
NO >> GO TO 2.
2.CHECK HO2S2 GROUND CIRCUIT

Is the inspection result normal? YES >> GO TO 3.
NO >> Repair or replace error-detected parts.
3.CHECK HO2S2 INPUT SIGNAL CIRCUIT


Is the inspection result normal? YES >> GO TO 4.
NO >> Repair or replace error-detected parts.
4.CHECK HEATED OXYGEN SENSOR 2
Check the heated oxygen sensor 2. Refer to EC-253, "Component Inspection".
Is the inspection result normal? YES >> Check intermittent incident. Refer to EX-5, "Exploded View".
NO >> GO TO 5.
5.REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2. Refer to EX-5, "Exploded View".
CAUTION:
>> INSPECTION END
Component Inspection
1.INSPECTION START
Do you have CONSULT? Do you have CONSULT? YES >> GO TO 2.
NO >> GO TO 3.
2.CHECK HEATED OXYGEN SENSOR 2
With CONSULT

“HO2S2 (B1)� should be above 0.73 V at least once when the “FUEL INJECTION� is + 25%.
“HO2S2 (B1)â€� should be below 0.18 V at least once when the “FUEL INJECTIONâ€� is − 25%.
Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 6.
3.CHECK HEATED OXYGEN SENSOR 2-1
Without CONSULT

Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 4.
4.CHECK HEATED OXYGEN SENSOR 2-2
Check the voltage between ECM harness connector and ground as per the following condition.

Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 5.
5.CHECK HEATED OXYGEN SENSOR 2-3
Check the voltage between ECM harness connector and ground as per the following condition.

Is the inspection result normal? YES >> INSPECTION END
NO >> GO TO 6.
6.REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2. Refer to EX-5, "Exploded View".
CAUTION:
>> INSPECTION END
P0138 HO2S2
P014C, P014D, P015A, P015B, A/F sensor 1Battery
How to Handle Battery
CAUTION:
If it becomes necessary to start the engine with a booster
battery and jumper cables, use a 12-volt
booster battery.
After connecting battery cables, ensure that they are tightly
clamped to battery terminals for good
contact.
Never ...
Consult/gst checking system
Description
NOTE:
This vehicle is diagnosed using the CONSULT-III plus.
When CONSULT is connected with a data link connector equipped
on the vehicle side, it will communicate with the control unit
equipped in the vehicle and then enable various kinds of diagnostic
tests.
Ho ...
Parking brake
WARNING
Be sure the parking brake is fully released
before driving. Failure to do so
can cause brake failure and lead to an
accident.
Do not release the parking brake from
outside the vehicle.
Do not use the shift lever in place of the
parking ...